A class of personal computers that is smaller than the typical “desktop” or “laptop” devices is known in the art as “tablet” personal computers, or tablet PCs. Such computing devices are generally known for use as personal digital assistants and as specialized, mobile computers. Tablet PC's typically offer the advantage of a small form factor that is easy for the user to carry.
The systems of known tablet PCs employ a variety of methods for mapping to buttons. Known methods for mapping to buttons in system implementations can differ from model to model and from one OEM/ODM to another. Although a small number of such features have been standardized by mapping methods such as, for example, ACPI, most are not standardized at all.
This requires that a new ACPI device driver be written every time, requiring the driver writer to coordinate with the BIOS developer to ensure that they agree on the names of the ACPI control methods and any parameters they might have.